Presently, in a case when an individual person enjoys certain services or follows the necessary procedures, the person is often required to prove that he/she is the right person qualified to enjoy the services or properly registered to enable him/her to follow the necessary procedures. At present, an individual person is also required to prove if a letter or any document such as an electronic mail which is transmitted over a network is justifiable. These actions are generally known as certification. That is, certification means any action to distinguish that a natural person (an individual person), a legal person, a group, an article, an apparatus, a letter or the like is not another person or a fake and proves that the person or the article is the right person or the genuine article.
Such certification can be classified into plural forms depending on its use or purpose. Among those, there is identification or authentication for identifying an individual person. The identification distinguishes natural person (an individual person) and confirms if he/she has a certain qualification or if he/she is the registered person.
Methods of such identification include not only by means of a certification medium having a face photograph of an individual person visibly attached thereto such as, for example, identification cards which are seen in driver's licenses, passports or the like, some of credit cards or the like but also by means of finger prints, retinas, irises, voiceprints, handwritings and other personal characteristic information. Another simple method of identification is by means of a fact of holding something such as a credit card. Furthermore, developed are new technologies which are combinations of such technologies as certification by passwords .commonly used in electronic commerce which is advanced in recent years as a result of popularization of network technology, certification by digital signature and other certification technologies.
In these identification technologies, it is important that individual persons are highly accurately distinguished. On the contrary to the need for highly accurate certification, however, there are conflicting requirements to perform identification at a low cost, to eliminate the need for a special device or the like for certification if possible, to enable to perform certification at any place, to minimize complicated certification procedures, or to relieve oppressive feeling to the individual person to be certified.
Technical evaluation of such certification technologies has been studied in various industries. For example, the certification technologies study WG (working group) in the Electronic Commerce Demonstration Promotion Council (currently the Electronic Commerce Promotion Council of Japan) publicly released the “Evaluation Standard of Identification Technology (Version 1)” in April 1998. Also, in March 2000, the Certification and Notary WG of the Council released the “Proposal on Certification Level and Identification System”.
Incidentally, holograms which are made by using holographic technology are difficult to copy or counterfeit as compared to printed materials prepared by a sublimation type or ink jet type printer or by an electro-photographic type copier, and thus are being used also for a certification purpose.
For example, holograms are visibly integrated into such anti-counterfeit articles as credit cards, employee certificates, and also bills, thereby improving counterfeit prevention capability of such articles.
However, in such certification technology which uses holograms with excellent anti-counterfeit capability, because of difficulty in making a large quantity of holograms and high cost of making so-called image holograms which can express halftones like photographs, it is popular to use embossed holograms which are less expensive and easy to reproduce in a large quantity.
Embossed holograms are made by providing unevenness on metal foils or polymer films and thus can be made at a low cost and in a large quantity by making an original mold which is then used as a press or a template. However, embossed holograms are very expensive in making an original mold, which are disadvantageous in cost when duplicating a small number such as less than several hundreds because the cost of making an original mold is a major portion of the total production cost including copied holograms.
Also, in holograms, in order to make original molds of holograms for a purpose of achieving a goal of free image expression, a so-called computer generated hologram (CGH) technique using a computer is often employed for calculating light wave surfaces and interference fringes. However, since the technologies for the computer generated holograms are not fully advanced yet, it can be reproduced by a monochromatic light such as a laser beam or the like and thus not in a stage of expressing sufficient tones like photographs.
In reproducing holograms using original molds made by such embossed holograms or the computer generated holograms, identical holograms can be reproduced in a large quantity. As a result, in certification technology using such holograms which are integrated into articles requiring anti-counterfeit capability, it is typical to integrate an identical hologram for, for example, one kind of credit card services, i.e., credit cards from the same credit brand, thereby integrating a common hologram for each kind.
However, since these holograms can be reproduced in a large quantity, it is possible that a large quantity of counterfeit articles are made if once a hologram corresponding to the original mold is counterfeited, thereby making it insufficient to use as certification of the articles integrating a common hologram for each kind.
As a part of a series of certification technologies using these embossed holograms or the computer generated holograms, proposed are various technologies for making anti-counterfeit articles and for certifying anti-counterfeit articles.
One of such technologies is disclosed in, for example, Japanese non-examined patent publication no. 2000-348145.
This technology is to make a stamper as an original mold from a group of holograms which can reproduce 300 kinds of images such as alphabets, numbers and then the stamper is used to form computer generated holograms on bare cards. Accordingly, in this technology, as described in the paragraph [0025] in the patent specification, bare cards made from a single stamper comprise computer generated holograms each having a data storage area of an identical format. In this technology, in a case where there are, for example, 10 computer generated holograms disposed in parallel in a data memory area, a technique is used to destroy 5 out of the 10 computer generated holograms for recording certification information exclusive to the card in the data memory area of the identical format.
In other words, in the technology, a duplicating type hologram which comprises computer generated holograms as an original mold is integrated with cards, and a part of the holograms are destroyed in order to record individual information. Accordingly, the technology does not overcome drawbacks of the conventional computer generated holograms, i.e., restricting the reproduction light to a monochromatic light such as a laser or the like and incapability of expressing sufficient tones like a photograph. In a case of using such technology, it is impossible to express images such as portraits and it is impossible to reproduce by using any desired illumination light such as white light.
Other technologies for making anti-counterfeit articles and for certifying anti-counterfeit articles are disclosed in, for example, Japanese non-examined patent publication no. 2000-348149.
This patent specification discloses an apparatus for issuing cards with holograms made by using the technology as disclosed in the above mentioned Japanese non-examined patent publication no. 2000-348145, a database associated with it, a device for reading out the holograms by illuminating a monochromatic light onto the issued cards, a certification apparatus for certifying by comparing the information acquired by reading out the holograms and the information held in the database, and a system comprising these apparatus and the like.
That is, these Japanese non-examined patent publication nos. 2000-348145 and 2000-348149 disclose a card which records individual information by integrating therein a duplicating type hologram which uses as its original mold a computer generated hologram reproducible by illuminating a monochromatic light and destroying a part of the hologram, and a certification technology using the card.
Moreover, a technique for making an anti-counterfeit article and for certificating an anti-counterfeit article is disclosed in, for example, Japanese patent no. 2906730.
This technique records numbers, characters, symbols and the like in a hologram as information pattern and attaches the hologram to a part of information medium. For example, an embossed hologram is used to record numbers, characters, symbols and the like similar to barcodes and magnetic patterns and are read out by using a coherent light. Accordingly, this patent publication also records information by integrating an embossed hologram (a relief hologram) with a card in such a manner to be reproduced by illuminating a monochromatic light.
Furthermore, a technique for making an anti-counterfeit article and for certificating an anti-counterfeit article is disclosed in, for example, Japanese non-examined patent publication no. Hei 11-339049.
This technique reads visible information such as photographs, signed characters or seals for identifying an individual person on a surface of a card as a multi-level image of n×m pixels and calculates a degree of coincidence in features by means of splitting the read-out image into plural blocks.
Also, a technique for making an anti-counterfeit article and certificating an anti-counterfeit article is also disclosed in, for example, Japanese non-examined patent publication no. Hei 11-66315.
This technique uses the same technique as those disclosed in the above Japanese non-examined patent publication no. Hei 11-339049 and reads out visible information as multi-level images. And a degree of coincidence of features is calculated by means of comparison in image levels between a certain pixel and circumference pixels of a read-out image.
That is, these Japanese non-examined patent publication nos. Hei 11-339049 and Hei 11-66315 disclose techniques which automatically compare visible information by designated device in order to identify individual persons.
Yet another technique for making an anti-counterfeit article and for certifying an anti-counterfeit article is disclosed in, for example, Japanese non-examined patent publication no. Hei 10-124642.
This technique is similar to conventional cash cards used in banks each having a memory portion for storing information therein and a display surface for displaying information except a hidden part of the information and a comparison is made by acquiring the non-displayed hidden information by inquiring to a card holder. The official gazette includes descriptions about encryption of the hidden information and insertion of unique information to the hidden information in the hope of more reliable anti-counterfeit capability.
Incidentally, these conventional certification techniques using a hologram as disclosed in these official gazettes are unable to reproduce the hologram by other than a monochromatic light. In certification procedures, an exclusive device is required for reproduction, thereby making the entire system expensive. And locations to perform certification are restricted, thereby making the certification procedures complicated. Since the articles to which these techniques are applied include information elements such as numbers, characters, symbols and the like recorded as the hologram, they are different from those for directly distinguishing individual persons for a certification purpose. Even if the article is genuine, in a case where it is stolen and a stealer pretends as if he/she is the right holder, it is difficult to discover a dishonest use.
The present invention was made in light of the foregoing circumstances. It is an object of the present invention to provide a certification system and a certification method which are capable of reliably and easily certifying individual persons by means of certification medium integrating visible information which is able to directly and easily distinguish individual persons, and yet satisfying requirements for performing certification at any desired location, minimizing complicated steps in certification, and minimizing oppressive feeling to individual persons to be certified. It is an additional object of the present invention to provide a certification medium manufacturing apparatus for making a certification medium to be used in a certification system, a certification method and also a certification terminal device for certifying by using the certification medium made by the certification medium manufacturing apparatus.